The biggest social security benefits shake-up in decades could cost Northern Ireland more than 1,600 jobs, an Assembly committee has been warned.

The mainly administrative jobs may be shed as a result of the more simplified system in which most benefits, including Disability Living Allowance, are being replaced by Universal Credit.

Now the SDLP has accused DUP Social Development Minister Nelson McCausland of attempting to deflect attention away from the job losses.

Union Nipsa said its research, based on the Social Development Department’s figures, estimate a total of 1,630 jobs — 35% of the workforce — will be lost.

MLA Mark Durkan said: “The minister and his party have continually tried to deflect the story away from these job losses.” Nipsa’s deputy general secretary Alison Millar told the committee the loss of jobs provided by the complex distribution of benefits would mean a knock-on effect of “£500m being removed from the Northern Ireland economy”.

A spokesman for Mr McCausland’s department said: “The department is carrying out work to understand the number of staff it will require once the reforms have been implemented. Staff and their representatives will continue to be updated.”